Now, a group of German, Israeli and British scientists and students have found that a gene-based approach offers promise for development of a treatment that can suppress these reactions, while not impairing memory itself.

In an article appearing as the cover story in the current issue of Molecular Psychiatry, a team of researchers from the Silberman Institute of Life Sciences at the Hebrew University of Jerusalem and the Max Planck Institute for Experimental Medicine in Goettingen, Germany, describe their work with mice who were subjected to stressful conditions.

The team discovered that this stress induces a change in the expression of the acetylcholinesterase gene. Under normal circumstances, this gene produces a vital protein that adheres to neuronal synapses (the interaction sites through which nerve cells communicate with each other). Following stress, however, the same gene produces large quantities of a protein with modified properties that results in heightened electrical signals in the nerve cells communicating through these synapses. The effect is to create reactions of extreme fright or immobilizing shock.

Later encounter with a context which arouses those stressful memories which might be an object, a sound, an image or other form of association -- can set off that same neuronal reaction. Often, this reaction can have serious consequences, such as chronic fatigue or personality disorders, including post- traumatic stress disorder (PTSD). In the U.S., it is estimated that more than 15 million people a year are identified with PTSD or other anxiety disorders.

The research team at the Hebrew University and in Germany and Britain has succeeded in developing an "antisense" agent that acts to neutralize the process whereby the modified pro
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Contact: Jerry Barach
jerryb@savion.huji.ac.il
972-2-588-2904
The Hebrew University of Jerusalem
11-Dec-2003